https://rocket703.github.io/evi/
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
88
GRADE
B
FIX
0
REVIEW
3
PASS
4
INFO
1
Checks
84 PASS 3 REVIEW
BCO2 Per Page Load0.55g CO2 per viewREVIEW
CO2 Per Page Load
0.55g CO2 per view
0.55g CO2 per view
Info::
0.55g CO2 per page view
This page transfers 2.3 MB, producing an estimated 0.55g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.11g, end-user device 0.42g.
Got: 0.55g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 65.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 65.9 kg of CO2 annually — equivalent to charging 8241 smartphones.
Info::
Green hosting reduces data center emissions
0.55g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 56% of websites
Sustainable Web Design model v4 · Page size: 2.3 MB
Your site
0.55g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.01g
Network
0.11g
End-user device
0.42g
At 10,000 monthly views: Monthly: 5.5 kg · Annual: 65.9 kg · ≈ 8241 smartphone charges
BCarbon Budget44th percentileREVIEW
Carbon Budget
44th percentile
44th percentile
Info::
0.55g CO2 — below the median website (0.60g)
Better than an estimated 56% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 44th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
0.55g
44th percentile
Cleaner than 56% of websites
✗ Above the median website
vs Median 8% cleaner ✓
vs Target 10% more
BWeb Font Weight VariantsNo detectable Google Fonts weightsREVIEW
Web Font Weight Variants
No detectable Google Fonts weights
No detectable Google Fonts weights
Info::
No detectable Google Fonts weights
The analyzer detects font weights via Google Fonts URL parameters (~70% of font-using sites). Self-hosted fonts and non-Google CDN fonts aren't visible to URL-based detection. If you self-host fonts, manually audit how many @font-face weights you ship -- 2-3 weights per family is typically enough; 5+ is usually unused payload.
A+Green HostingGreen (both)PASS
Green Hosting
Green (both)
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: GitHub Pages, CDN: GitHub Pages
Info::
GitHub Pages: Verified by the Green Web Foundation
Info::
GitHub Pages: Hosted on Azure/GitHub with Microsoft carbon-negative commitment
Info::
Green hosting status based on known provider commitments
Green hosting detection uses a curated database of provider renewable energy commitments. This is not a real-time verification. For authoritative checks, visit thegreenwebfoundation.org.
Green Hosting✓ Green Hosted
Hosting GitHub Pages✓CDN GitHub Pages✓
GitHub Pages: Verified by the Green Web Foundation
GitHub Pages: Hosted on Azure/GitHub with Microsoft carbon-negative commitment
Based on known provider commitments. Verify at thegreenwebfoundation.org
A+Repeat Visit Weight99% cachedPASS
Repeat Visit Weight
99% cached
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 19 KB (vs 2377 KB first visit). 26 of 27 resources are served from browser cache, saving 0.54g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.55g)
First visit
2377 KB
Repeat visit
19 KB
99% reduction on repeat visits
Saving 0.54g CO2 per returning visitor
26 resources served from cache · 1 resources re-downloaded
A+Transfer Efficiency100% efficientPASS
Transfer Efficiency
100% efficient
100% efficient
Info::
Transfer efficiency: 100%
Only 0 KB of potential savings identified. Your page is well-optimized for size.
Actual transfer 2377 KB
Theoretical minimum 2377 KB
See Deep Analysis sections above for specific optimizations.
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
Whether the site is served from green-energy infrastructure
Green Hosting
This site is hosted on green energy infrastructure
Provider: Fastly
Image Optimization26 images, 537 KB total, 12 KB wastedINFO
Image Optimization
26 images, 537 KB total, 12 KB wasted
Image Optimization Audit
Total Images
26
Total Size
537 KB
Oversized
1
Wasted
12 KB
2 missing dimensions 2 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.